Houston winters are short, and that is exactly the problem. A furnace sits unused for about 8 months, then gets asked to fire up cold and run all night when the first November front comes through. A good number of the no-heat calls we run after the first freeze are on furnaces that "got tuned up" a month earlier.
So what belongs in a real tune-up? Below is the list we work from.
The 16 points
This is the heating half of the 34-point inspection on our membership page. The cooling tune-up covers the other 18.
Burners, gas and venting
- Remove and clean the burners. Rust and debris collect over a summer of sitting, and dirty burners light unevenly.
- Check and adjust burner operation, so the flame burns the way the manufacturer intends.
- Check manifold gas pressure with a manometer. Low pressure means poor combustion, which brings soot and CO. High pressure overfires the equipment and is hard on the heat exchanger.
- Check for natural gas leaks at the furnace connections.
- Check the heat exchanger. A crack here can let carbon monoxide into the house.
- Check and clean the flue, so combustion gases leave the house and don't back up into it.
Ignition and safety controls
- Inspect the thermocouple and igniter. Between them they cause a big share of mid-winter no-heat calls, and replacing a weak one in October is the whole point of the visit.
- Check the high-limit control, the safety that shuts the burner off if the heat exchanger overheats.
- Check the fan control, so the blower comes on and shuts off when it should.
Blower, electrical and controls
- Check and adjust the blower components. A dirty or worn blower moves a lot less air. If the wheel needs pulling and cleaning, that is an extra charge, and we tell you before we start.
- Lubricate all moving parts that take oil.
- Check all electrical connections. A loose one heats up and arcs until it melts, and plenty of techs skip it.
- Check thermostat calibration, beyond whether it turns on.
- Check the heat anticipator, so the furnace doesn't short-cycle or overshoot.
- Check the air filter and replace it if it's dirty.
- Clean and wash the heater exterior. A clean cabinet makes the next leak or scorch mark easy to spot.
What the $59 special usually does
If your tune-up took less than 45 minutes, here is what almost certainly didn't happen:
- The burners stayed in the furnace
- No gas pressure reading
- No real look at the heat exchanger
- No actual readings, only a sticker
- No written record of values to compare against next year
Loss-leader pricing like that exists to get a tech in the door to look for an upsell. The tune-up itself is mostly for show.
What about heat pumps?
A heat pump burns no fuel, so the combustion items drop off. In their place goes a refrigerant cycle inspection: subcooling and superheat readings, a defrost cycle test, a check of the reversing valve and a look at how clean the outdoor coil is. Different list, about the same time on site.
What you should ask before you book
Before you commit to any tune-up, ask:
- "Will I get a written report?"
- "Do you pull and clean the burners and check the heat exchanger?"
- "How long is a typical visit?"
- "What's not included that might be an extra charge?" (Blower wheel cleaning, capacitor replacement, IFC board work, etc.)
Vague or rushed answers are your cue to call someone else. If your furnace is past 10 years old and has only ever had the sticker version, get a full tune-up this fall. There's a good chance it turns up something the cheap visits missed.
Our heating tune-up is $99, or $79 with our website coupon, and it ends with a written report in your hand. Clear Advantage members get it included. Call 281-992-7866 or book a tune-up.